A similar snapshot survey was obtained in the near-infrared on a sample of 23 sources[1]} using the PIONIER[2]} instrument on the VLTI.
Using a set of geometrical models with increasing complexity it was possible to show that the near-infrared size/stellar luminosity relation found for young stellar objects[3]}, [4]}, can be extrapolated to the high-luminosities that are typical for post-AGB stars (\(10^3-10^4\)  L\(_\odot \) ).
This demonstrates that the inner dusty rims of disks around post-AGB binaries are not ruled by dynamical truncation due to the inner binary but by dust sublimation.
Those near-infrared sizes of the environment are, however, slightly larger than in protoplanetary disks likely because of different dust chemistry and/or gas density in the dust sublimation region.
This is corroborated by the slightly lower environmental temperatures measured using the spectral channels of the PIONIER instrument.
The other main conclusion of this survey was that complex geometric models (more than 13 parameters) are favoured for most (\(>\) 55%) targets.
This suggests a high intrinsic complexity of the target morphologies in the near-infrared.
There is, therefore, a risk of being model biased when trying to reproduce the complex interferometric signal provided by 4-telescope infrared interferometric instruments.
With the advent of instruments being able to combine more and more telescopes in the infrared, interferometric image reconstruction techniques are perfect to solve this problem and to reveal the origin of the complexity of these targets.
